Pneumatic action.



C. I. JOHNSON. FNEUMATIC ACTION. I APPLICATION FILED IAN.24l |914.1,157,398. Patented 001.1111915.

2 SHEETS-SHEET I.

*Iz/J2, 1,

C. J. JOHNSON.

PNEUMATIC ACTION.. APPLICATION FILED IAN.24. I9I4.

Patented Oct. 915.

2 SHEETS-S EET 'OLUIIIA HAMIAFH C0., www. D. C.

CHARLES J. JGHNSON, GF CT-CLCTC,

PNEUMLTIC ATGN.

1,157,398 Specification of Letters Eats-nt.

Application filed anuary 555.-, 1314:. serial 11e.

To all 1li/tom t may concern.' against the top of the corresponding airBe it known that l, @Hann-ns J. lor-inscri, chamber by i eans of a plate1S as india citizen of the United States, and a resident cated. arrangedin board 1G inmiediately of the city of Chicago, county of Coolr, and in"iront of each of the chambers Ll is an in- 60 5 State of lllinois, haveinvented certain new termit'ent vacuum cnamcer 19 which is sepand usefulImprovements in Pneumatic ricrated from chamber 8 by means of aflextions, of which the following is a specificaible diaphragm 20, eachof the chambers 19 tion. being connected by a passage 21 in top board Myinvention relates to improvements in 13 with the flexible tube 22leading to the 65 pneumatic actions especially adapted for usual trackerboard of the player piano. use in player pianos and has for its objectArranged across he upper front portion of the provision of an improvedconstruction board 1G is a bleeder vacuum chamber 23 of this characterwhich is simple and etliwhich is in constant communication with cient inuse. each of the chambers 19 through a minute 70 rlhe invention consistsin the combinableeder opening 211. fr rod 25 is slidably tions andarangements of parts hereinafter mounted in a suitable bracket Q6 andcondescribed and claimed. tacts with the corresponding diaphragm 2G Theinvention will be best understood by and the corresponding valve 15, sothat inreference to the accompanying drawings ward movement of diaphragm2G into cham- 75 20 forming a part of this specification, and in ber 8will raise valve 11j from its seat and which swing valve 16 to its seat.

Figure 1 is a face view of a portion of the ln operation a vacuum ismaintained in pneumatic action of a player piano shown each of thechambers 8 and Q3 in the usual with portions broken away and others inmanner. l/hen air is admitted to any one 80 section, and Fig. 2 is asection taken on line of the chambers 19 through the correspondmofFig. 1. ing tube 22 from the tracker board of the The preferred form ofconstruction as piano, the vacuum normally maintained in illustrated inthe drawings comprises a plusaid chamber 19 is wholly or partiallyderality of bellows 1, each having a movable stroyed and diaphragm 2O isdrawn in- 85 side :2 connected. with a separate operating wardly inchamber S by the vacuum mainrod 3, each of the rods B being adapted totained therein. rhis opens the correspondoperate one note of a pianotnot shown). ing valve 15 and closes the correspondingrlhe bellows 1 arepreferably arranged in valve so that a vacuum is also formed in threerows, but connected to operate indethe corresponding chamber il causingcol- 35 pendently of each other. An air chamber lapse of the bellows 1and elevation of the 4e is arranged adjacent each of the bellows rodThis upward movement of rod 3 1 and in open communication with the outisits operative stroke. l/Vhen the admisside atmosphere through a passage6 and a sion of air through tube is discontinued,

port 7 as shown. A vacuum chamber 8 is the constant bleeding or passageof air 95 arranged across the front of the bellows 1 through minuteopening 21 into chamber 2B ancL air chambers 4 and a port 9 leads fromrestablishes a vacuum in the corresponding chamber 8 into each of theair chamchamber 19 and as soon as the pressure in bers 4. The vacuumchamber 8 is formed chamber 19 falls below that of the outside rearboard 11 which are spaced apart at the on valve 1G combined with gravitywill open bottom by means, of astrip 12 and are said valve 1G and closevalve 15 thus resecured together at the top by means of a storing theparts to original normal conditop board 13. An angular valve head 'lilis tion.

arranged in each of the chambers and carrlhe arrangement disclosed is asimple and ries two valves 15 and 16, valve 15 being efficient one forthe purpose, very compact arranged to hold the corresponding port 9 inform, is practically unaffected by changes normally closed and valve 1Gbeing arin temperature and therefore is highly etliranged to close portl when valve head 14 cient in use.

swings to open port 9. Valve head 1-1 is lhilel have illustrated anddescribed the 110 mounted upon a piece of flexible fabric 17, preferredform of construction for carrysuch as rubber cloth, and secured in placeing my invention into effect, this is capable in a space between a frontboard 10 and a atmosphere the pressure of the atmosphere 100.

of variation and modification without Vdeparting from the spirit of theinvention. I, therefore, do not wish to be limited to the precisedetails of construction set forth, but desire to avail myseli2 of suchvariations and modifications as come within the scope of the appendedclaim.

Iavino Vdescribed m invention what I claim as new and desire to secureby Letters Patent is:

pneumatic action comprising` an air chamber having` ports in adjacentwalls thereof; a swinging` valve head carrying two valves in iiXedrelation to Veach other and Copies of this patent may be obtained forfive cents each, by addressing the Commissioner controlling said ports,said valve head being supported by a flexible member secured to a wallof said air Chamber by means of a removable plate; and means Vforswinging said valve head to cause said valves to oontrol said ports toe'eot operation of said pneumatic, substantially as described.

In testimony whereof I have signed my name to this specification in thepresence of two subscribing witnesses.

' CHAR-LES J. JOHNSON.

Witnesses:

JOSHUA R. H. PoTTs, ARTHUR A. OLSON.

of Patents.

Washington, D. C.

